Process for the preparation of polyquinazolones



United States Patent O U.S. Cl. 260-47 9 Claims ABSTRACT OF THE DISCLOSURE Polyquinazolones which may be shaped to form fibers, films and other shaped articles are prepared by reacting a diacylated aromatic diaminodicarboxylic acid such as a dicylated bisanthranilic acid with a diprimary diamine such as 4,4-diaminodiphenylether.

BACKGROUND OF THE INVENTION The present invention relates to a process for the preparation of condensation polymers, and more particularly, to a process for the preparation of linear polyquinazolones.

Since their discovery, linear condensation polymers such as the polyamides and polyesters have found wide application in the plastic industry in the form of fibers, films and molded articles. The polyamides described in Wallace H. Carothers U.S. Patents 2,071,250 and 2,071,- 253, issued Feb. 16, 1937, and U.S. Patent 2,130,948, issued Sept. 20, 1938, for example, are tough, wear resistant, resilient, stable polymers, useful over a wide range of conditions. However, the search for improved polymers having higher stiffness and toughness, higher softening points, better retention of stiffness at elevated temperatures, improved resistance to water and oxygen, has continued. The present invention was made as the result of the search for such improved polymers.

SUMMARY OF THE INVENTION Accordingly, the primary object of the present invention is to provide a process for the preparation of polyquinazolones. This and other objects will be apparent from the following description.

In accordance With the present invention, polyquina- Zolones are prepared by reacting a diacylated aromatic diaminodicarboxylic acid, wherein each carboxy group has a vicinal acylated amino group, with a diprimary diamine.

The essence or heart of the present invention is the discovery that the diacylated aromatic diaminodicarboxylic acid does not have to be dehydrated in a separate step prior to reaction with the diamine, but that it can be dehydrated concurrently with its reaction with the diamine.

DETAILED DESCRIPTION OF THE INVENTION (A) Diacylated aromatic diaminodicarboxylic acid O in all RON NC R IIOOC COOII wherein R is aliphatic, cycloaliphatic or aromatic, preferably aromatic; and wherein R is aromatic.

When R is an aliphatic group it is preferably one having from 1 to 10 carbon atoms, most preferably 1 to 3 carbon atoms; and when R is a cycloaliphatic group it is preferably one having from 5 to 8 carbon atoms. As mentioned above, R is preferably aromatic, for example, phenyl. The aliphatic, cycloaliphatic and aromatic groups may be substituted, provided the substituents do not interfere in the reaction with the diamine.

With reference to R, it may be a monoor poly-nuclear aromatic group such as F m O \J] I) I wherein R" is aliphatic, preferably containing from 1 to 6 carbon atoms; aromatic; CO; SO O-; -N-; or the like.

Preferably R is monoaromatic or dimonoaromatic. The R aromatic group may also contain inert substituents, i.e., substituents which do not interfere in the reaction of the diacylated acid with the diamine.

Suitable specific examples of the diacylated aromatic diaminodicarboxylic acids which may be used in the pres ent invention are bis-(acylamino)-terephthalic acid; bis- (acylamino)-phthalic acid; bis-(acylamino)-isophthalic acid; bis-(acylamino)-diphenyl dicarboxylic acid; bis- (acylamino)-naphthalene dicarboxylic acid; and preferably, dibenzoyl-bisanthranilic acid (3,3'-dicarboxy dibenzoyl benzidine); 4,6-dibenzoylaminoisophthalic or 2,5- dibenzoylaminoterephthalic acid.

The diacylated aromatic diaminodicarboxylic acid may be conveniently prepared by diacylating the aromatic diaminodicarboxylic acid via any of the well known acylation processes. For example, the aromatic diaminodicarboxylic acid may be heated to a temperature of up to about 50 C. in the presence of an aqueous solution. to which is added benzoyl chloride. The manner in which the diacylated acid is acylated or prepared does not form a part of the present invention.

(B) Diamine The diamines which are reacted with the diacylated acids heretofore described are diprimary diamines, including hydrazine. The diprimary diamines may possess a general formula where R' is aliphatic, aromatic, cycloaliphatic, CO-, SO or a covalent bond.

Suitable aliphatic diprimary diamines possess a formula where n equals 2 to about 10. Illustrative examples of such aliphatic diprimary diamines include: 1,2-diaminoethane; 1,3-diaminopropane; 1,4-diaminobutane; ,1,5-diaminopentane; and 1,6-diaminohexane (hexamethylene diamine).

Suitable aromatic diprimary diamines include: 1,2-diaminobenzene (ortho-phenylene diamine); 1,3-diaminobenzene (meta-phenylene diamine); 1,4-diamino-benzene (p-phenylene-diamine); 2,4-diaminotoluene; 2,6-diaminotoluene; 1,5 diaminonaphthalene; 1,8 diaminonaphthalene; 3,3-dimethylbenzidine; tetramethyl-p-phenylenediamine; 4,4 diaminodiphenylether and bis-(p-aminophenyl) methane.

Suitable cycloaliphatic diprimary diamines include: ment with hydrolytic and oxidizing media, and an ability 1,4-cyclohexanediamine; and 4,4-methylenebiscyclohexto withstand continued exposure to elevated temperatures. ylamine. The polymers may, for example, be dissolved in concen- The preferred diprimary diamines are aromatic and are trataed sulfuric acid and recovered without degradation represented by the formula by dilution with water. Solubility in concentrated sulfuric m acid is not surprising for polymeric materials, but this 2 medium normally rapidly degrades polymers.

wherein is Polyquinazolones prepared in accordance with this invention may be shaped to form fibers, films, and other shaped articles of wide utility. In the case of some of these polymers, melt temperatures are low enough that shaping may be accomplished directly from the melt. Where melt temperatures are too high for melt shaping, solutions may or be prepared from which shaped articles may be formed. A Many of the polymers are soluble in such solvents as formic acid, concentrated sulfuric acid, dimethyl sulfoxide and N,N-dimethyl-formamide, forming stable solutions which are especially well suited for the casting of films and the spinning of fibers. In the form of films and Z being a lower alkyl group having from 1 to 5 carbon fibers, the polymers continue to exhibit their stability to atoms; oxygen; or covalent b h aromatic i high temperatures and their resistance to hydrolytic and may also contain inert substituents such as lower alkyl 'd g media, g y enhancing their utilitygroups having from 1 to 5 carbon atoms. Bis-(p-amino- The invention is additionally illustrated by the following phenyl) methane and 4,4-diaminodiphenylether are par- F x mpl ticularly preferred aromatic diprimary diamines. EXAMPLE I The polyqurnazolones of the present invention are formed by reacting equimolar quantities of one of the A stirred reaction vessel was charged with 15.9 grams above described diacylated acids with one of the above of 3,3'-dicarboxybenzidine dissolved in 600 mls. of Water described diamines, for example, by reacting equimolar and 12 mls. (14.1 grams) of benzoyl chloride. A soluquantities of diacylated bisanthranilic acid with 4,4'-dition of 12 grams of NaOH dissolved in mls. of Water aminodiphenylether, as exemplified by the following rewas added slowly to the vessel with rapid stirring whereaction: by the temperature rose to about 28 C. After about 15 l i f I? R-CN- Q 0 'NCR HZN o- O NH2 HOOC OOOH The reaction of the diacylated acid with the diamine minutes, acetic acid was added to the mixture causing is conducted at a temperature of above about 200 C., the product dibenzoyl-bisanthranilic acid to precipitate preferably from about 250 to 350 C. out as a solid. The precipitate was recovered by filtration The reaction is conducted in the presence of an inert 50 and washed with water. It was recrystallized from dimethatmosphere of nitrogen, argon or the like in order to preylacetamide.

vent the oxidation of the diamine. Any convenient pres- A stirred reaction vessel was charged with 2.4 grams sure may be used during the reaction, atmospheric or subof the above dibenzoyl-bisanthranilic acid and 1.0 gram atmospheric pressures being preferred in order to recover of 4,4-diamino diphenylether. The materials were reacted the water of condensation in its vapor state. under a nitrogen atmosphere at a temperature of about If desired, a dehydrating agent such as sodium sulfate 200 to 330 C. for about 7 hours to yield a polyquinazomay also be employed during the reaction in order to lone resin.

assist the condensation polymerization. The resulting polyquin-azolone resin had an inherent vis- The diacylated acid may be reacted with the diamine cosity of 0.22 as measured in dimethylacetamide, and it in any conventional type of stirred, liquid-liquid, liquidwas stable at 425 C. and 525 C. in N and air, respecsolid, or solid-solid reaction or polymerization zone, detively.

Pending 011 the Particular diacylated acid or diamine The polyquinazolone obtained had the following eleployed, on a continuous, semi-continuous or batch basis. mental analysis Preferably, a mass or bulk polymerization reaction system A nalysis Ca1cu1ated: C 783%; H, 397%; N,

is employed. However, if desired, the diacylated acid and 5 9.21% Found: C 75.4%; H 392%. N

diamine may be dissolved in a highly polar solvent such The principle, preferred embodinient and mode of if g l g i g ii orlhexalpeglyl' operation of the present invention have been described in p 05p oraml e an Su lee e 0 so u Ion P0 ymenza 1011' the foregoing specification. However, it should be under- Under the above mentioned conditions, the polymerization reaction of the diacylated acid with the diamine stoofl that the Whlch Intended to herein, may be practiced otherwise than as described withis normally completed in about 0.5 to 100 hours, preferably 3 t 10 h out departing from the scope of the appended claims.

The product polyquinazolone polymers formed by the We Claim! process of the present invention are characterized by a 1. A process for the preparation of polyqurnazolones,

high degree of stability, showing great resistance to treatwhich comprises heating at a temperature of above about 200 C. equimolar amounts of a diacylated aromatic diaminodicarboxylic acid of the formula is t RON NCR HOOC COOH wherein R is aromatic, R is selected from the class consisting of an aliphatic group, a cycloaliphatic group and an aromatic group, and wherein each carboxy group is vicinal to an acylated amino group with a diprimary diamine to yield the desired polyquinazolone.

2. The process of claim 1, wherein the diprimary diamine is of the formula wherein R'" is selected from the class consisting of a covalent bond, an aliphatic group, a cycloaliphatic group and an aromatic group, and the resulting polyquinazolone consists of recurring units of the formula liLtl wherein R is aromatic, R is selected from the class consisting of an aliphatic group, a cycloaliphatic group and an aromatic group, and wherein each carboxy group is vicinal to an acylated amino group with a diprimary di- 3. The process of claim 2, wherein R is aromatic. 4. The process of claim 3, wherein R is aromatic and is selected from the class consisting of wherein R is selected from the class consisting of CO, $Og, -O-, N, an aliphatic group, and an aromatic group.

5. A process for the preparation of polyquinazolones, which comprises reacting equimolar amounts of a diacylated aromatic diaminodicarboxylic acid of the formula OH HO U u R N NCR HOOO COOH wherein R and R are aromatic groups, and wherein each carboxy group is vicinal to an acylated amino group with a diprimary diamine of the formula where R'" is an aromatic group, said reaction being conducted at a temperature above about 200 C. for a period of time in the range of from about 0.5 to hours to yield a polyquinazolone consisting of recurring units of the formula 6. The process of claim 5, wherein R is a phenyl group. 7. The process of claim 6, wherein R is aromatic and is selected from the class consisting of wherein R" is selected from the class consisting of CO, -SO --O, --N, an aliphatic group, and an aromatic group.

8. The process of claim 7, wherein the diprimary diamiine is of the formula H N--R"NH wherein R' is selected from the class consisting of Z being selected from the class consisting of a lower alkyl group having 1 to 5 carbon atoms, oxygen, and a covalent bond.

9. The process of claim 5, wherein the diacylated aromatic diaminodicarboxylic acid is dibenzoyl-bisanthranilic acid and the diprimary diamine is 4,4-diaminodiphenylether.

and

US. Cl. X.R. 26065, 78 79.3 

